1. The Structure of Na2W2O7·1/2H2O Synthesized under High Pressure and Temperature
- Author
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Dahlborg, Magnus Åsberg, Svensson, Göran, and Valkeapää, Markus
- Subjects
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POLYTUNGSTATES , *X-ray diffraction - Abstract
A new compound, Na2W2O7·1/2H2O, has been found in the Na2O–WO3–H2O system. It is the fourth compound in the Na2W2O7·
x H2O system and the second phase containing water. The crystals were prepared at a pressure of 1.5 GPa and a temperature of 900°C. Na2W2O7·1/2H2O, has been found in the Na2O–WO3–H2O system. It is the fourth compound in the Na2W2O7·xH2O system and the second phase containing water. The crystals were prepared at a pressure of 1.5 GPa and a temperature of 900°C. Na2W2O7·1/2H2O crystallizes in the triclinic space group, P1¯, Z=2, with lattice constants of a=8.4902(6) A˚, b=7.6636(6) A˚, c=5.1501(3) A˚, α=91.959(7)°, β=96.521(8)° and γ=111.678(7)°. The structure is built up from double chains of WO6 octahedra running along c, interconnected by two-dimensional nets of NaO6 polyhedra. Sodium coordinates to six oxygens forming both octahedra and trigonal prisms. [Copyright &y& Elsevier] - Published
- 2002
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